Hydraulic Lift II. The piston of a hydraulic automobile lift is 0.30 m in diameter. What gauge pressure, in pascals, is required to lift a car with a mass of 1200 kg? Also express this pressure in atmospheres.

Solution 24E To find the pressure required to lift the car Step 1: Mass of the car m = 1200 kg Diameter of the piston d = 0.3 m or radius r = 0.15 m Acceleration due to gravity g = 9.8 m/s 2 Gauge Pressure p-p = F 0 A Step 2: F is the equivalent downward force (weight) applied by car F = mg F = 1200x9.8 F = 1.18 x 10 N 4 Step 3: A is the area of the piston 2 A = r A = 3.1415x(0.15 ) 2 A = 0.071 m 2